[genocidicbunny]

There's an inherent power disparity though. There's a high probability the slumlord has more resources than you, and he's not beholden to his 'opponent' providing his housing. So it's not likely your average renter has the capability to address these kinds of problems, which means you need some sort of power structure that has a mandate to enforce such things. Thus, laws and bans on certain behaviours and actions.

[sokoloff]

Yes, there are already laws against slumlording in most places already. It's not on an individual renter to hold the power, but on a licensing or health/building code enforcement government agency to prevent uninhabitable or sub-standard housing from being rented without recourse. The tenant just has to complain to them and the government comes down with the power.

Not counting college, I've rented at 7 different places, representing about 13 years in total. None were slums. All were far better than me having to buy an entire place each time I wanted to move somewhere.

Remove slums? Hell yes! Remove rental properties? Hell no!